In recent years, wireless communication apparatuses are provided with RF antennas such as an antenna for telephone communication, an antenna for GPS, an antenna for wireless LAN/BLUETOOTH (registered trademark), and RFID (Radio Frequency Identification). Examples of an electric power transfer system to be used in the mode of a contactless charging system include an electromagnetic induction system, a radio wave receiving system, and a magnetic resonance system. Any of these systems makes use of electromagnetic induction or magnetic resonance between a primary coil and a secondary coil, and, for example, NFC (Near Field Communication) standards for RFID make use of electromagnetic induction.
It has been proposed that, in such short-distance wireless communication systems, for example, an antenna module is built in a portable electronic device, such as a smart phone or a tablet, and the portable electronic device serves as a transponder to receive a magnetic field from an external reader/writer, such as an automatic wicket machine, a key for office access, or a terminal for counter settlement, and perform data communication. Alternatively, it has been also proposed that a portable electronic device serves as a reader/writer to cause an IC card or an IC tag having an external antenna module incorporated therein to transmit a magnetic field, and thereby to read card information or tag information.